Tunnel notcher and guidewire delivery device

ABSTRACT

A tunnel notcher and guidewire delivery device is provided for creating a notch and positioning a guidewire within a bone tunnel. In general, the device includes an elongate member having proximal and distal ends with an inner lumen extending therebetween that is adapted to receive a guidewire. The device also includes a cutting element disposed on a distal portion of the elongate member that is adapted to remove bone within an opening of a bone tunnel. In use, the device  10  can be at least partially positioned within a bone tunnel containing a bone plug, and it can be manipulated to form a notch within or adjacent to an opening of the bone tunnel using the cutting element  18 . The device  10  is also effective to deliver a guidewire  16  to the bone tunnel at a location adjacent to the notch.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a divisional application of U.S. patent applicationSer. No. 10/708,467, entitled TUNNEL NOTCHER AND GUIDEWIRE DEVICE, filedMar. 5, 2004, which is incorporated herein by reference.

FIELD OF THE INVENTION

The present invention relates to methods and devices for repairing tornand/or damaged tissue, and in particular to methods and devices forcreating a notch and positioning a guidewire within a bone tunnel.

BACKGROUND OF THE INVENTION

Ligaments are tough bands of tissue which serve to connect the articularextremities of bones, or to support or retain organs in place within thebody. Ligaments are typically composed of coarse bundles of dense whitefibrous tissue which are disposed in a parallel or closely interlacedmanner, with the fibrous tissue being pliant and flexible, but notsignificantly extensible.

In many cases, ligaments are torn or ruptured as a result of accidentsor overexertion. Accordingly, various procedures have been developed torepair or replace such damaged ligaments. For example, in the humanknee, the anterior and posterior cruciate ligaments (i.e., the ACL andPCL) extend between the top end of the tibia and the bottom end of thefemur. The ACL and PCL cooperate, together with other ligaments and softtissue, to provide both static and dynamic stability to the knee. Often,the ACL is ruptured or torn as a result of, for example, asports-related injury. Consequently, various surgical procedures havebeen developed for reconstructing the ACL so as to restore normalfunction to the knee.

In many instances, the ACL may be reconstructed by replacing theruptured ACL with a graft ligament. More particularly, with suchprocedures, bone tunnels are typically formed in the top end of thetibia and the bottom end of the femur, and one end of the graft ligamentis positioned in the femoral bone tunnel and the other end of the graftligament is positioned in the tibial bone tunnel. The graft ligamentthus extends between the femur and the tibia in substantially the sameway, and with substantially the same function, as the original ACL,thereby allowing the graft ligament to cooperate with the surroundinganatomical structures so as to restore normal function to the knee.

When anchoring a graft ligament to the tibia and the femur, the two endsof the graft ligament are typically attached to an anchoring member,such as a bone plug, that is inserted into a bone tunnel. Bone screws orsimilar fasteners are often used to maintain each bone plug within itsrespective tunnel. Such a procedure typically requires a recess to beformed in the bone adjacent to the bone tunnel to allow the bone screwto be inserted alongside the bone plug. The recess serves as a “starterhole” for the bone screw so that the screw can engage bone in agenerally proper direction with respect to the bone tunnel. As the bonescrew is threaded into the bone, the resulting interference fit betweenthe bone plug and the bone screw secures the graft ligament in place inthe bone tunnel.

Since ACL repair is typically performed arthroscopically, the currentprocedure for forming a bone recess requires the surgeon to estimate thebest location for positioning the bone screw adjacent to the bone plug.In particular, current devices for forming a recess in a bone tunnelhave a relatively large size that requires that the recess be formedbefore the bone plug is inserted into the tunnel, thus the surgeoncannot determine the best location for the recess, and consequently forthe bone screw, in relation to the bone plug. Once the recess is formed,a guidewire must be positioned between the anchoring member and asidewall of the bone tunnel for delivering a bone screw to the tunnel ata location adjacent to the recess. Since the guidewire is deliveredafter formation of the notch, the position of the guidewire is oftenestimated as well. Accordingly, these methods and devices can result inmisalignment of the bone screw, thus resulting in a high rate ofdivergence between the bone screw and the bone tunnel, and often in aloss of bone plug fixation within the bone tunnel. Unfortunately,screw/tunnel divergence is usually only identified postoperatively viaradiographs, and the loss of bone plug fixation cannot be readilycorrected, thereby resulting in an unsuccessful repair of a rupturedACL.

Thus, there remains a need for improved methods and devices for creatinga notch and positioning a guidewire within a bone tunnel to provide anaccurate, secure, and trouble-free fixation of a ligament within thebone tunnel.

SUMMARY OF THE INVENTION

The present invention generally provides a tunnel notcher and guidewiredelivery device for creating a notch and positioning a guidewire withina bone tunnel. In one embodiment, the device includes an elongate memberhaving proximal and distal ends with an inner lumen extendingtherebetween and adapted to receive a guidewire. The device alsoincludes a cutting element that is disposed on a distal portion of theelongate member and that is adapted to remove bone within an opening ofa bone tunnel. A handle member can be disposed on or mated to a proximalportion of the elongate member. The device can also optionally include alocking mechanism that is adapted to lock a guidewire extending throughthe lumen in the elongate member in a releasably fixed position withrespect to the elongate member. The locking mechanism can include, forexample, a threaded member, such as a set screw, that is disposed withina threaded bore formed in the handle. The threaded bore is incommunication with the inner lumen of the elongate member and it allowsthe set screw to secure the guidewire in the releasably fixed position.

The cutting element on the elongate member can be disposed at a varietyof locations on the device, but in one embodiment, it is located on adistal portion of the distal end of the elongate member, and morepreferably it is disposed proximal to the distal end of the elongatemember. The cutting element can also have a variety of configurations,shapes, and sizes, but in an exemplary embodiment it is substantiallywedge-shaped and extends distally outward from the elongate member. Inan exemplary embodiment, the cutting element includes a distal-facingsurface that is positioned at an acute angle with respect to alongitudinal axis of the elongate member. More preferably, the cuttingelement is adapted to create a notch in bone having a substantiallysemi-circular shape such that the notch is effective to facilitateplacement of a bone screw within a bone tunnel for securing a bone plugtherein.

The present invention also provides methods for preparing a bone tunnel.In one embodiment, the method includes the steps of positioning a tunnelnotcher and guidewire delivery device between a bone plug and a sidewallof a bone tunnel and manipulating the device such that the cuttingelement removes a portion of bone to create a notch in or adjacent to anopening of the bone tunnel. The tunnel notcher and guidewire deliverydevice is then removed leaving a guidewire positioned between the boneplug and the bone tunnel adjacent to the notch. A bone screw can then bedelivered along the guidewire to engage bone at the notch, and therebysecure the bone plug within the bone tunnel.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be more fully understood from the following detaileddescription taken in conjunction with the accompanying drawings, inwhich:

FIG. 1 is a perspective view of one embodiment of a tunnel notcher andguidewire delivery device according to the present invention;

FIG. 2A is an enlarged view of a cutting element on the tunnel notcherand guidewire delivery device shown in FIG. 1;

FIG. 2B is a side, cross-sectional view of the cutting element shown inFIG. 2A taken along a longitudinal axis of the tunnel notcher andguidewire delivery device;

FIG. 2C is an end view of the tunnel notcher and guidewire deliverydevice shown in FIG. 1;

FIG. 3A is cross-sectional view of a locking mechanism on the tunnelnotcher and guidewire delivery device shown in FIG. 1;

FIG. 3B is a cross-sectional view of the locking mechanism shown in FIG.3A in the locked position;

FIG. 4A is an illustration of a human knee having a bone tunnel formedtherein;

FIG. 4B is an illustration of the human knee shown in FIG. 4A with atunnel notcher and guidewire delivery device in accordance with thepresent invention being introduced into the bone tunnel;

FIG. 4C is an illustration showing the tunnel notcher and guidewiredelivery device of FIG. 4B disposed within the bone tunnel to removebone, forming a notch within the opening of the bone tunnel;

FIG. 4D is an illustration showing the tunnel notcher and guidewiredelivery device of FIG. 4C removed from the bone tunnel, leaving a guidewire positioned within the bone tunnel adjacent to the notch; and

FIG. 4E is an illustration showing a bone screw being delivered alongthe guide wire shown in FIG. 4D to the bone tunnel in accordance withanother embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

The present invention provides a device for creating a notch in a bonetunnel, and for positioning a guidewire within the bone tunnel. Ingeneral, as shown in FIG. 1, the device 10 includes an elongate member12 having an inner lumen 12 c extending therethrough and adapted toreceive a guidewire 16. A cutting element 18 is formed on or adjacent toa distal portion 13 of the elongate member 12, and it is effective toremove bone within or adjacent to an opening of a bone tunnel. Thedevice 10 can also include a handle 14 mated to or formed on a proximalend 12 a of the elongate member 12 for grasping the device 10. In use,the device 10 can be at least partially positioned within a bone tunnelcontaining a bone plug, and it can be manipulated to form a notch withinor adjacent to an opening of the bone tunnel using the cutting element18. The device 10 is also effective to deliver a guidewire 16 to thebone tunnel at a location adjacent to the notch. The guidewire 16 cansubsequently be used to deliver a fastening element, such as a bonescrew, to the notch, thus allowing the bone screw to be threaded intothe bone tunnel to secure the bone plug or other anchoring member withinthe tunnel.

The methods and devices of the present invention are particularlyadvantageous in that they allow a surgeon to remove bone to form a notchwithin or adjacent to an opening of a bone tunnel after a bone plug orother anchoring member has been positioned in the bone tunnel, therebyensuring proper positioning of the notch and subsequently of a fasteningelement with respect to the bone plug. The device 10 also eliminates theadditional step of positioning a guidewire after the notch is formedsince the guidewire is implanted using the tunnel notcher and guidewiredelivery device, thus further providing proper alignment of the bonescrew with the notch and the bone plug or other anchoring memberdisposed within the bone tunnel.

Still referring to FIG. 1, the elongate member 12 of the tunnel notcherand guidewire delivery device 10 can have a variety of configurations,shapes, and sizes. As shown in FIG. 1, however, the elongate member 12has a generally hollow cylindrical shape and it includes proximal anddistal ends 12 a, 12 b with an inner lumen 12 c extending therebetweenfor slidably receiving a guidewire 16. The length l_(e) of the elongatemember 12 can vary, but it should be sufficient to allow the proximalend 12 a of the elongate member 12 to remain outside a patient's bodywhile the distal end 12 b is positioned within a bone tunnel, preferablybetween a bone plug or other anchoring member and a sidewall of the bonetunnel.

The proximal end 12 a of the elongate member 12 preferably has a handle14 mated thereto or formed thereon to facilitate grasping the device 10.While the handle 14 can have any shape and size, FIG. 1 illustrates agenerally elongate handle 14 that extends in a direction that issubstantially transverse to a longitudinal axis L of the elongate member12. Opposed gripping portions 14 a, 14 b, can be formed on the handle 14to conform to a user's fingers. In particular, a distal-facing surface15 of each gripping portion 14 a, 14 b, can be substantially concave forseating one or more fingers of the user. This allows the user to graspthe device 10 by positioning their fingers around the handle 14 so as toform a fist. A person skilled in the art will appreciate that a varietyof handles or other devices can be used to facilitate grasping of thedevice 10.

The distal end 12 b of the elongate member 12 can also have a variety ofconfigurations, but it should be adapted to be positioned between a bonetunnel and a bone plug or other anchoring member. The distal end 12 b isalso preferably configured such that at least a portion of it can beinserted into the bone tunnel to a particular depth to facilitate thecorrect positioning of the cutting element 18 with respect to the bonetunnel. In an exemplary embodiment, shown in FIGS. 2A and 2B, the distalend 12 b has a tapered tip 20 such that a diameter of the tip 20decreases in a proximal to distal direction. This facilitates insertionof the distal end 12 b between the sidewall of the bone tunnel and theanchoring member. The distal end 12 b can also include markings 22 orother indicia disposed or formed thereon, as shown in FIGS. 1 and 2A, toindicate an insertion depth of the distal end 12 b of the elongatemember 12 into a bone tunnel. The markings 22, which are preferablylocated proximal to the cutting element 18, can optionally extendcircumferentially around the elongate member 12 to facilitate visualaccess thereof. In an exemplary embodiment, the markings 22 areradio-opaque to allow x-ray visualization thereof during an arthroscopicprocedure.

As previously stated, the device 10 also includes a cutting element 18that is formed on a distal portion 13 of the elongate member 12. Thecutting element 18, which is shown in more detail in FIGS. 2A-2C, canhave any configuration and it can be disposed anywhere on the elongatemember, but it should be effective to remove bone to form a notchadjacent to or within an opening of a bone tunnel. In an exemplaryembodiment, as shown, the cutting element 18 is positioned proximal tothe distal end 12 b of the elongate member 12, preferably just proximalto the tapered tip 20, to allow the tapered tip 20 to be disposed into abone tunnel between a sidewall of the bone tunnel and a bone plug orother anchoring member disposed therein. The cutting element is alsopreferably disposed on one side of the elongate member 12, such that itis offset from the longitudinal axis L of the elongate member 12. Inparticular, the cutting element 18 can have a length l_(c) (FIG. 2C)that is less than or equal to a diameter D of the elongate member 12.Such a configuration will allow the cutting element 18 to remove bonefrom the bone tunnel without coming into contact with and/or causingdamage to the bone plug or other anchoring member disposed within thebone tunnel.

The shape and size of the cutting element 18 can also vary, but in anexemplary embodiment it is substantially wedge-shaped such that it has awidth w_(c) that increases in a proximal to distal direction. A baseportion 18 b of the cutting element 18 is mated to or formed on theelongate member 12, and a cutting edge 18 a is positioned a distance dapart from the elongate member 12. The distance d (FIG. 2C) between thecutting edge 18 a and the elongate member 12 can vary, but it should besufficient to allow a portion of bone adjacent to or within a bonetunnel to be removed such that a notch is created for receiving a bonescrew. The cutting edge 18 a is also preferably positioned at a locationthat is distal of the base portion 18 b with respect to the longitudinalaxis L of the elongate member 12. This can be achieved by providing adistal-facing surface 18 c on the cutting element 18 that extendsbetween the cutting edge 18 a and the elongate member 12, and that ispositioned at an acute angle α with respect to the longitudinal axis Lof the elongate member 12. While the angle α can vary, in an exemplaryembodiment, the angle α is in the range of about 20° to 70°. Thedistal-facing surface 18 c can also optionally be substantially concavesuch that opposed edges 19 a, 19 b of the cutting element 18 formcutting edges that are effective to remove bone.

In another embodiment, the cutting edge 18 a can have a substantiallyarcuate shape, such that the distance d between the cutting edge 18 aand the elongate member 12 remains substantially constant along theentire length l_(c) of the cutting edge 18 a. Such curvature of thecutting edge 18 a will facilitate removal of bone, and in particular itwill allow a semi-circular notch to be formed in bone.

As previously stated, the tunnel notcher and guidewire delivery device10 includes an inner lumen 12 c that extends through the elongate member12 and the handle 14 for receiving a guidewire. Since the guidewire ispreferably positioned within the inner lumen 12 c during use of thedevice 10, the device 10 can optionally include a locking mechanism 24formed thereon for maintaining a guidewire in a fixed position relativeto the elongate member 12. While a variety of locking mechanisms knownin the art can be used, FIGS. 1 and 3A-3B illustrate an exemplaryembodiment of a locking mechanism 24 that is formed on the handle 14 ofthe elongate member 12. As shown, the locking mechanism 24 is in theform of a set screw 28 that is disposed within a threaded bore 26 formedin handle 14. The threaded bore 26 is in communication with the innerlumen 12 c of the elongate member 12. In use, as shown in FIG. 3B, theset screw 28 can be threaded into the threaded bore 26 to engage aguidewire 16 that is disposed within the inner lumen 12 c of theelongate member 12, thereby locking the guidewire 16 in a fixedposition.

The tunnel notcher and guidewire delivery device 10 of the presentinvention can be used in a variety of medical procedures for preparing abone tunnel for receiving a fastening element, such as a bone screw, tosecure an anchoring member disposed within the bone tunnel. In anexemplary embodiment, however, the device 10 is used to prepare a bonetunnel for anchoring a ligament therein, and in particular forarthroscopic femoral fixation of an anterior cruciate ligament (ACL)graft, as shown in FIGS. 4A-4E. While various graft ligaments can beused, the graft ligament (not shown) is typically prepared by separatingthe graft into four tendon bundles, each of which is prepared by whipstitching a length of suture thereto. Two anchoring members, such asbone plugs, are then attached at each end of the ligament.

An incision is then made, following medically acceptable patientpreparation and anesthetization, near the end of the tibial bone 52below the patella, and a bone tunnel 56 is formed through the tibial andfemoral bones 52, 54. For illustration purposes, FIGS. 4A-4E only show abone tunnel 56 formed in the femoral bone 54, however, a person skilledin the art will appreciate that the device and methods of the presentinvention can be inserted through either or both of the femoral andtibial bones. One end of the graft ligament, i.e., the leading end, isthen passed through the tibial tunnel into the femoral tunnel 56, andthe other end of the graft ligament, i.e., the trailing end, remainsoutside of the tibial bone tunnel, thus permitting access through thetibial tunnel to the femoral tunnel 56. Again, for illustrationpurposes, FIGS. 4A-4E only show a bone plug 53 disposed within thefemoral bone tunnel 56, and a graft ligament is not shown.

In preparation for use, a guidewire 16 is inserted through the device 10of the present invention, preferably such that a portion of theguidewire 16 extends from the distal end 12 b of the elongate member 12to facilitate insertion of the distal tip 20 of the device 10 into thebone tunnel 56 between the bone plug 53 and a sidewall of the bonetunnel 56. The guidewire 16 is preferably locked in fixed position byrotating the set screw 28 of the locking mechanism 24. Since mostguidewires are relatively flexible, it is preferable to only have asmall portion of the guidewire 16 extend from the distal end 12 b of theelongate member 12 to provide rigidity to the guidewire 16.

The device 10 can then be inserted through the tibial bone tunnel 56 toposition the tapered tip 20 of the elongate member 12 between the boneplug 53 and the femoral bone tunnel 56, as illustrated in FIGS. 4B and4C. A mallet or other impacting tool can optionally be used to furtherimpact the device 10 to advance it into the area between the bone plug53 and the bone tunnel 56 to a desired depth. The radio-opaque markings22 near the distal end 12 b of the elongate member 12 can be used toindicate when the device 10 is at the correct depth.

Once properly positioned, the device 10 is partially rotated about itslongitudinal axis L such that cutting edge 18 a of the cutting element18 moves in a semi-circular direction, thereby removing a portion ofbone to create a notch 58. As shown in FIG. 4D, the notch 58 is formedwithin or adjacent to an opening of the bone tunnel 56. After creatingthe notch 58, the locking mechanism 24 is released by rotating the setscrew 28 in the opposite direction, allowing the device 10 to be removedwhile leaving the guidewire 16 positioned within the bone tunnel 56, asillustrated by FIG. 4D, between the bone plug 53 and adjacent to thenotch 58.

A fastening element, such as a bone screw 80, as shown in FIG. 4E, canthen be delivered by sliding the screw 80 along the guidewire 16 towardthe notch 58. An insertion tool or driver mechanism 70, as shown, canoptionally be used to advance the screw 80 along the guidewire 16, andto thread the screw 80 into the bone tunnel 56. When the bone screw 80is positioned adjacent to the bone tunnel 56, the notch 58 will allowthe threads of the bone screw 80 to engage the bone, and thus furtherrotation of the screw 80 will secure the bone plug 53 in the bone tunnel56.

One skilled in the art will appreciate further features and advantagesof the invention based on the above-described embodiments. Accordingly,the invention is not to be limited by what has been particularly shownand described, except as indicated by the appended claims. Allpublications and references cited herein are expressly incorporatedherein by reference in their entirety.

What is claimed is:
 1. A method for preparing a bone tunnel, comprising:inserting a bone plug into a bone tunnel; positioning a tunnel notcherand guidewire delivery device between the bone plug and a sidewall ofthe bone tunnel, the tunnel notcher comprising an elongate member withan inner lumen extending therethrough, a guidewire passing through thelumen, and further comprising a cutting element having a distal bonecutting edge disposed proximal to a distal portion of the elongatemember, the cutting edge facing distally and being entirely spaced awayfrom and not normal to the elongate member; removing a portion of bonewith the cutting edge to create a notch in an opening of a bone tunnel,the notch being effective to facilitate placement of a bone screw withinthe bone tunnel for securing the bone plug therein; and removing thetunnel notcher and guidewire delivery device such that the guidewireremains positioned between the bone plug and the bone tunnel adjacent tothe notch.
 2. The method of claim 1, wherein the notch has asubstantially semi-circular shape.
 3. The method of claim 1, furthercomprising delivering a bone screw along the guidewire to engage bone atthe notch, and to secure the bone plug within the bone tunnel.
 4. Themethod of claim 1, wherein the guidewire is disposed within the tunnelnotcher and guidewire delivery device during positioning of the tunnelnotcher and guidewire delivery device between the bone plug and the bonetunnel.
 5. The method of claim 4, wherein the guidewire is in areleasably fixed position with respect to the tunnel notcher andguidewire delivery device during positioning of the tunnel notcher andguidewire delivery device between the bone plug and the bone tunnel. 6.The method of claim 5, further comprising a locking mechanism formed onthe tunnel notcher and guidewire delivery device and adapted toreleasably fix the guidewire with respect to the tunnel notcher andguidewire delivery device.
 7. The method of claim 6, wherein the lockingmechanism is coupled to a handle formed on the tunnel notcher andguidewire delivery device.
 8. The method of claim 7, wherein the lockingmechanism comprises a threaded member disposed within a threaded boreformed in the handle, the threaded bore being in communication with aninner lumen formed in the tunnel notcher and guidewire delivery deviceand containing the guidewire.
 9. The method of claim 1, wherein a distalportion of the tunnel notcher and guidewire delivery device issubstantially tapered to allow the distal portion to be positionedbetween the bone plug and the sidewall of the bone tunnel.
 10. Themethod of claim 1, wherein the cutting element extends distally outwardfrom the tunnel notcher.
 11. The method of claim 10, wherein the cuttingelement is substantially wedge-shaped and includes a distal-facingsurface that is disposed at an acute angle with respect to alongitudinal axis of the tunnel notcher.
 12. The method of claim 11,wherein the angle is less than 90°.
 13. The method of claim 1, furthercomprising a plurality of indicia formed on a distal portion of thetunnel notcher and guidewire delivery device and adapted to indicate adepth of the tunnel notcher and guidewire delivery device within a bonetunnel.